In a medium mixing bowl combine the ground pork, minced onion, oyster sauce, egg, soy sauce, ginger, and pepper. Mix until incorporated and set aside.
In a large soup pot, combine beef broth, water and 1 tablespoon of the beef bouillion. Bring to a simmer and taste for flavor. If you would like a deeper, beefy flavor add an additional tablespoon of beef bouillion.
While the broth is coming to a simmer fill your wonton wrappers with a heaping 1/2 teaspoon of filling and seal. (See the video below.)
After tasting the broth, gently drop in the finished wontons. The wontons will cook in just a few minutes and will float to the top when finished.
Serve the soup in bowls and garnish with sliced green onion. If you have any wonton wrappers leftover, you can cut them into strips and lightly fry them. Drain and sprinkle over the soup for an added crunch.